#define _CRT_SECURE_NO_WARNINGS 1
#include<iostream>
using namespace std;
int f(int x, int y)
{
	if (x == 3 || y == 4)
		return 1;
	return f(x + 1, y) + f(x, y + 1);
}

int main()
{
	cout << f(0, 0) << endl;
	return 0;
}